Singer Lee Greenwood surprised President Trump on Sunday night by performing his classic song "God Bless the USA" -- which Trump starts every one of his rallies with -- live to a packed house at his rally in Chattanooga, Tennessee for Republican Senate candidate Marsha Blackburn.

Greenwood got massive cheers and shook Trump and Pence's hands on stage during his performance.

"God bless our president and our vice president," Greenwood said at the end of his performance, throwing in a salute to Trump.

"Where do you begin?" Trump said after Lee's performance. "I didn't know Lee Greenwood would be here, that was a surprise! Wow, we love that voice and we love that song!"

"Thank you, Lee!"

"I know I speak for everyone where when I say, indeed, we are proud to be Americans!" Trump said to cheers.

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Rush Limbaugh, Sean Hannity and Lee Greenwood are going to be at Trump's rally in Cape Girardeau, Missouri on Monday.